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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
301

Transitions Between Hover and Level Flight for a Tailsitter UAV

Osborne, Stephen R. 23 July 2007 (has links) (PDF)
Vertical Take-Off and Land (VTOL) Unmanned Air Vehicles (UAVs) possess several desirable characteristics, such as being able to hover and take-off or land in confined areas. One type of VTOL airframe, the tailsitter, has all of these advantages, as well as being able to fly in the more energy-efficient level flight mode. The tailsitter can track trajectories that successfully transition between hover and level flight modes. Three methods for performing transitions are described: a simple controller, a feedback linearization controller, and an adaptive controller. An autopilot navigational state machine with appropriate transitioning between level and hover waypoints is also presented. The simple controller is useful for performing a immediate transition. It is very quick to react and maintains altitude during the maneuver, but tracking is not performed in the lateral direction. The feedback linearization controller and adaptive controller both perform equally well at tracking transition trajectories in lateral and longitudinal directions, but the adaptive controller requires knowledge of far fewer parameters.
302

Attitude Estimation and Maneuvering for Autonomous Obstacle Avoidance by Miniature Air Vehicles

Hall, James K. 22 December 2008 (has links) (PDF)
Utilizing the Euler-Rodrigues symmetric parameters (attitude quaternion) to describe vehicle orientation, we develop a multiplicative, nonlinear (extended) variation of the Kalman filter (MEKF) to fuse data from low-cost sensors. The sensor suite is comprised of gyroscopes, accelerometers, and a GPS receiver. In contrast to the common approach of using the complete vehicle attitude as the quantities to be estimated, our filter states consist of the three components of an attitude error vector. In parallel with the time update of the attitude error estimate, we utilize the gyroscope measurements for the time propagation of the attitude quaternion. The accelerometer and the GPS sensors are used independently for the measurement update portion of the Kalman filter. For both sensors, a vector arithmetic approach is used to determine the attitude error vector. Following each measurement update, a multiplicative reset operation moves the attitude error information from the filter state into the attitude estimate. This reset operation utilizes quaternion algebra to implicitly maintain the unity-norm constraint. We demonstrate the effectiveness of our attitude estimation algorithm through flight simulations and flight tests of aggressive maneuvers such as loops and small-radius circles. We implement an approach to aerobatic maneuvering for miniature air vehicles (MAVs) using time-parameterized attitude trajectory generation and an associated attitude tracking control law. We designed two methodologies, polynomial and trigonometric, for creating functions that specify pitch and roll angles as a function of time. For both approaches, the functions are constrained by the maneuver boundary conditions of aircraft position and velocity. We construct a trajectory tracking feedback control law to regulate aircraft orientation throughout the maneuvers. The trajectory generation algorithm was used to construct several maneuvers and trajectory tracking control law successfully executed the maneuvers in the flight simulator. In addition to the simulation results, MAV flight tests verified the performance of the maneuver generation and control. To achieve obstacle avoidance maneuvering, the time parameterized trajectories were converted to spatially parameterized paths, which allowed for inertial reference frame position error to be included in the control law feedback loop. We develop a novel method to achieve the spatial parameterization using a prediction and correction approach. Additionally, the first derivative of position of the desired path is modified using a corrective parameter scheme prior to being used in the control. Using the path position error and the corrected derivative, we utilize a unit-norm quaternion framework to implement a proportional-derivative (PD) control law. This control law was demonstrated in simulation and hardware on maneuvers designed specifically to avoid obstacles, namely the Immelmann and the Close-Q, as well as a basic loop.
303

SMEs’ Absorptive Capacity in the Context of Innovation Labs : An Exploratory Study about SMEs in the Context of ILs and the Integration Process of Acquired Knowledge

Nolte, Yvonne Madeleine, Nordberg, Gustav January 2022 (has links)
In today’s fast-changing business climate, the priority on digital transformation demands organizations to develop innovation competencies to survive (Nambisan et al., 2017). To gain knowledge and know-how and stay innovative, organizations could work together with an Innovation Lab (IL) to remain competitive. To reach the best outcome from an IL, the dynamic between lab environment, resources, participants, and facilitation must be considered. Since SMEs typically have fewer resources, having an in-house IL is impossible. In addition, they require the guidance of experts to cope with the challenges of the digital era, to uncover solutions and continuous advancements, as innovation is critical for established companies to stay relevant in the phase of disruption and change (Berglund, 2007). This study aims to deepen the understanding of the phenomenon of ILs in the context of SMEs. More precisely, we are scrutinizing the integration of acquired knowledge, inventions, competencies, and innovations to see what both ILs and SMEs could do to achieve a better outcome. This study aims to originate valuable insights on integration patterns and key issues SMEs face during the IL, to fill literature gaps and build on existing theories of ILs (Fecher et al., 2020) and absorptive capacity (Zahra & George, 2002). Our goal is to contribute with managerial implications for SMEs who wish to participate in ILs and achieve a favorable outcome. Additionally, to give IL facilitators suggestions on making the process more suitable for SMEs. Our research aimed to answer the question of how SMEs integrate competencies and inventions developed during their IL participation in ILs. We established a multiple case study (Eisenhardt, 1989) to investigate the phenomenon. Together with existing literature and qualitative data, we set a model on: ‘SMEs’ Absorptive Capacity in the Context of Innovation Labs’. Our model describes how ACAP is present in the three lab phases and its effect on integrating competencies and inventions. First, our results show the relevance of preparation and participants in the pre- lab phase. Second, PACAP, including acquisition and assimilation, correlated with resources and the IL process in the lab phase. Third, in the post-lab phase or integration phase, RACAP with the capabilities of transformation and exploitation were significant for the business practice, IL process, IC, and resources. Concluding, each of the phases and SMEs’ capabilities during the IL process affects the integration and commercialization of the outcome.
304

Modeling copper pollution from road Runoff in a peri-urban catchment in Portugal by using MIKE SHE, and MIKE 11 coupled with ECO Lab

Valencia Gudiño, Ricardo January 2017 (has links)
Economic development in an area attracts more people to live in it. This increment drives the necessity to improve available infrastructure, like roads for instance, to satisfy a higher demand. Bigger roads and higher number of vehicles have raised the concern about possible pollution coming from these sources In this thesis, copper coming from road runoff in a peri-urban catchment in Portugal was analyzed. The catchment is located in the Coimbra region, center of Portugal. In order to model copper pollution in road runoff, it is necessary to couple a hydrological model and a water quality Based on a previous study (Kalantari, Ferreira, Walsh, Ferreira, & Destouni, 2017) a physical based hydrological model  MIKE SHE  coupled with the hydraulic model MIKE 11was updated and further coupled with  ECO Lab to simulate water quality and ecological processes. The results show an improvement of the hydrological model compared with the original one, nash-sutcliffe efficiency was raised from 0.59 to 0.77 and the coefficient of determination varied from 0.64 to 0.79. For copper the model behavior for punctual and distributed sources was analyzed. For punctual sources, highest concentrations were present in the grid points where the incoming sources were located in the tributaries, and these concentrations are rapidly reduced downstream. On the other hand, distributed sources approach gives higher concentrations near the end of the river than in the tributaries upstream. Comparing time-averaged model results along the river, with fresh water quality criteria according to U.S. EPA (2004), for punctual sources an extension of 978 meters (7,6% of the river) presents a concentration above CCC or CMC, on the contrary, for distributed sources the extension is lower with 494 meters (3,8%). The organic carbon partitioning coefficient have bigger influence on the results than other factors, nevertheless this influence is not marked. Modeled copper values do not agree well with the mesured values specially for periods with higher discharge as the model simulates lower concentration with higher discharge and viceversa. Copper boundary values for the model represent a big challenge considering limited data available. This thesis gives good overview about the coupling process between MIKE 11 and ECO Lab, as well as analyzes the importance of some factors as well as model limitations and uncertainties.
305

The Citizen Lab : A collaborative design exploration of citizenship / The Citizen Lab : A collaborative design exploration of citizenship

Mehta, Tanu January 2023 (has links)
In this thesis I explore how design makes and unmakes citizenship through a collaborative independent project together with design student Théo Löfgren. I start out by looking at how the Swedish administrative levels of governance unmake citizenship by designing the Swedish citizens into customers. This has consequences since costumers have no obligations towards the collective, thus affecting sustainability on all levels (social, cultural, economical and ecological). Through my collaborative independent project I wanted to use design to critique that citizens are being designed into customers, as well as to create a design that promotes a citizenship of rights and obligations by co-creation. The result is a prototype of an interactive space called the Citizen Lab in which we (me and Théo Löfgren) use provotypes to create a discussion about the ‘customer citizen’ and the approach of participatory design to engage citizens in co-creation. The Citizen Lab was staged at the city library of Malmö (‘Malmö Stadsbibliotek’). In collaboration with the library and The Enforcement Authority (‘Kronofogden’) participants of the lab got to speculate about the future connected to problems and possibilities suggested by the collaborators. In the end the Citizen Lab proved to be a space in which participants could engage in co-creation as well as a place for us to try out our design and methods which were iterated on during the staging.
306

Single Cell Impedance Measurements Using Microfabricated Electrodes and Labview Graphical Programming

Hernandez, Stephanie Sophia 01 December 2009 (has links) (PDF)
This Master’s Thesis project consists of the research, design, and fabrication of a system that could perform broadband impedance measurements (1kHz-20Mhz) of single cells using National Instruments Labview data acquisition and programming in coordination with a single cell capture device. Presented first is the background information on cells and their electrical properties, along with background in micro-total-analysis systems as well as impedance spectroscopy. Experimental Methods are then discussed for the electrode design, cellular modeling in COMSOL, fabrication methods, and Labview 8.0 Set-up and programming. Measurements were performed using the single-cell capture device on saline, yeast cells, and a polysterene bead. Analysis of the impedance data showed a clear visual and statistically significant difference between live yeast, the bead, and saline. A comparison of live yeast cells to nutrient-starved yeast cells was also performed and a distinct difference in spectra was observed.
307

INTERWEAVE - Food production interweaving with cultural programs, housing, and public places in Slakthusområdet, Stockholm.

Ratin, Md January 2023 (has links)
Slakthusområdet, a historically significant slaughterhouse district in Stockholm, stands as a testament to the dynamic nature of urban landscapes, characterized by the relentless tide of rapid urban change. Over the years, this district has undergone multiple transformations, mirroring the shifting needs and aspirations of the city. Currently, Slakthusområdet finds itself on the cusp of yet another metamorphosis, as a proposal takes shape to rejuvenate the area into a vibrant hub that seamlessly integrates housing, workplaces, commerce, services, and green spaces.Traditionally, Slakthusområdet served as a focal point for the slaughter and meat packaging industry, bearing witness to the relentless rhythm of production. However, the winds of change blow through the district once again, igniting a collective imagination that envisions its potential to become a sustainable and culturally diverse urban food production system. This transformative project seeks to explore new frontiers in food production, harnessing the possibilities offered by emerging technologies and innovative practices.Among the innovative modes of food production to be integrated into the fabric of Slakthusområdet are insect farming, vertical farming, and lab-based food production. By embracing these cutting-edge approaches, the project aims to revolutionize the way food is grown, cultivated, and distributed within the urban context. The district's existing buildings, with their deep-rooted historical significance, will be preserved and thoughtfully integrated with new construction, forming a dynamic juxtaposition of the old and the new. This fusion of heritage and modernity will serve as a powerful metaphor, embodying the district's journey of transformation and adaptation.Drawing inspiration from Slakthusområdet's rich history, the project seeks to unlock its hidden potential by interweaving food production with other essential elements of urban life. Housing, cultural organizations, and public spaces will converge harmoniously, creating a tapestry of activity and fostering a sense of community. By embracing a holistic approach to urban planning, the project aspires to create a new identity for Slakthusområdet that transcends the boundaries of a traditional urban district. By blending the realms of food production, sustainable living, and cultural vibrancy, Slakthusområdet can become a beacon of inspiration and a model for resilient, inclusive urban environments. The integration of emerging food production methods within an urban fabric is a novel endeavor with the potential to reshape our cities, fostering self-sufficiency, reducing environmental impacts, and promoting social cohesion.In conclusion, the proposed redevelopment of Slakthusområdet signifies a pivotal moment in the district's storied history. By embracing a vision that interweaves sustainable food production, housing, cultural organizations, and public spaces, the project strives to carve a new path forward. Through this transformation, Slakthusområdet can emerge as a shining example of urban regeneration, one that transcends its historical legacy and embraces the challenges and opportunities of the future. As the project sets in motion, its impact on urban design and planning practices will reverberate far beyond the boundaries of Stockholm, inspiring the cities of tomorrow to cultivate resilience, foster inclusivity, and nurture sustainable urban ecosystems.
308

Microfluidic Lab-on-a-Chip for Studies of Cell Migration under Spatial Confinement

Sala, Federico, Osellame, Roberto, Käs, Josef A., Martínez Vázquez, Rebeca 22 February 2024 (has links)
Understanding cell migration is a key step in unraveling many physiological phenomena and predicting several pathologies, such as cancer metastasis. In particular, confinement has been proven to be a key factor in the cellular migration strategy choice. As our insight in the field improves, new tools are needed in order to empower biologists’ analysis capabilities. In this framework, microfluidic devices have been used to engineer the mechanical and spatial stimuli and to investigate cellular migration response in a more controlled way. In this work, we will review the existing technologies employed in the realization of microfluidic cellular migration assays, namely the soft lithography of PDMS and hydrogels and femtosecond laser micromachining. We will give an overview of the state of the art of these devices, focusing on the different geometrical configurations that have been exploited to study specific aspects of cellular migration. Our scope is to highlight the advantages and possibilities given by each approach and to envisage the future developments in in vitro migration studies under spatial confinement in microfluidic devices.
309

3D Printed Microfluidic Devices for Bioanalysis

Beauchamp, Michael J 01 July 2019 (has links)
This work presents the development of 3D printed microfluidic devices and their application to microchip analysis. Initial work was focused on the development of the printer resin as well as the development of the general rules for resolution that can be achieved with stereolithographic 3D printing. The next stage of this work involved the characterization of the printer with a variety of interior and exterior resolution features. I found that the minimum positive and negative feature sizes were about 20 μm in either case. Additionally, micropillar arrays were printed with pillar diameters as small as 16 μm. To demonstrate one possible application of these small resolution features I created microfluidic bead traps capable of capturing 25 μm polystyrene particles as a step toward capturing cells. A second application which I pioneered was the creation of devices for microchip electrophoresis. I separated 3 preterm birth biomarkers with good resolution (2.1) and efficiency (3600 plates), comparable to what has been achieved in conventionally fabricated devices. Lastly, I have applied some of the unique capabilities of our 3D printer to a variety of other device applications through collaborative projects. I have created microchips with a natural masking monolith polymerization window, spiral electrodes for capacitively coupled contactless conductivity detection, and a removable electrode insert chip. This work demonstrates the ability to 3D print microfluidic structures and their application to a variety of analyses.
310

Hydrogel-based logic circuits for planar microfluidics and lab-on-a-chip automation

Beck, Anthony 25 September 2023 (has links)
The transport of vital nutrient supply in fluids as well as the exchange of specific chemical signals from cell to cell has been optimized over billion years of natural evolution. This model from nature is a driving factor in the field of microfluidics, which investigates the manipulation of the smallest amounts of fluid with the aim of applying these effects in fluidic microsystems for technical solutions. Currently, microfluidic systems are receiving attention, especially in diagnostics, \textit{e.g.} as SARS-CoV-2 antigen tests, or in the field of high-throughput analysis, \textit{e.g.} for cancer research. Either simple-to-use or large-scale integrated microfluidic systems that perform biological and chemical laboratory investigations on a so called Lab-on-a-Chip (LoC) provide fast analysis, high functionality, outstanding reproducibility at low cost per sample, and small demand of reagents due to system miniaturization. Despite the great progress of different LoC technology platforms in the last 30 years, there is still a lack of standardized microfluidic components, as well as a high-performance, fully integrated on-chip automation. Quite promising for the microfluidic system design is the similarity of the Kirchhoff's laws from electronics to predict pressure and flow rate in microchannel structures. One specific LoC platform technology approach controls fluids by active polymers which respond to specific physical and chemical signals in the fluid. Analogue to (micro-)electronics, these active polymer materials can be realized by various photolithographic and micro patterning methods to generate functional elements at high scalability. The so called chemofluidic circuits have a high-functional potential and provide “real” on-chip automation, but are complex in system design. In this work, an advanced circuit concept for the planar microfluidic chip architecture, originating from the early era of the semiconductor-based resistor-transistor-logic (RTL) will be presented. Beginning with the state of the art of microfluidic technologies, materials, and methods of this work will be further described. Then the preferred fabrication technology is evaluated and various microfluidic components are discussed in function and design. The most important component to be characterized is the hydrogel-based chemical volume phase transition transistor (CVPT) which is the key to approach microfluidic logic gate operations. This circuit concept (CVPT-RTL) is robust and simple in design, feasible with common materials and manufacturing techniques. Finally, application scenarios for the CVPT-RTL concept are presented and further development recommendations are proposed.:1 The transistor: invention of the 20th century 2 Introduction to fluidic microsystems and the theoretical basics 2.1 Fluidic systems at the microscale 2.2 Overview of microfluidic chip fabrication 2.2.1 Common substrate materials for fluidic microsystems 2.2.2 Structuring polymer substrates for microfluidics 2.2.3 Polymer chip bonding technologies 2.3 Fundamentals and microfluidic transport processes 2.3.1 Fluid dynamics in miniaturized systems 2.3.2 Hagen-Poiseuille law: the fluidic resistance 2.3.3 Electronic and microfluidic circuit model analogy 2.3.4 Limits of the electro-fluidic analogy 2.4 Active components for microfluidic control 2.4.1 Fluid transport by integrated micropumps 2.4.2 Controlling fluids by on-chip microvalves 2.4.3 Hydrogel-based microvalve archetypes 2.5 LoC technologies: lost in translation? 2.6 Microfluidic platforms providing logic operations 2.6.1 Hybrids: MEMS-based logic concepts 2.6.2 Intrinsic logic operators for microfluidic circuits 2.7 Research objective: microfluidic hydrogel-based logic circuits 3 Stimuli-responsive polymers for microfluidics 3.1 Introduction to hydrogels 3.1.1 Application variety of hydrogels 3.1.2 Hydrogel microstructuring methods 3.2 Theory: stimuli-responsive hydrogels 3.3 PNIPAAm: a multi-responsive hydrogel 4 Design, production and characterization methods of hydrogel-based microfluidic systems 4.1 The semi-automated computer aided design approach for microfluidic systems 4.2 The applied design process 4.3 Fabrication of microfluidic chips 4.3.1 Photoresist master fabrication 4.3.2 Soft lithography for PDMS chip production 4.3.3 Assembling PDMS chips by plasma bonding 4.4 Integration of functional hydrogels in microfluidic chips 4.4.1 Preparation of a monomer solution for hydrogel synthesis 4.4.2 Integration methods 4.5 Effects on hydrogel photopolymerization and the role of integration method 4.5.1 Photopolymerization from monomer solutions: managing the diffusion of free radicals 4.5.2 Hydrogel adhesion and UV light intensity distribution in the polymerization chamber 4.5.3 Hydrogel shrinkage behavior of different adhesion types 4.6 Comparison of the integration methods 4.7 Characterization setups for hydrogel actuators and microfluidic measurements . 71 4.7.1 Optical characterization method to describe swelling behavior 4.7.2 Setup of a microfluidic test stand 4.8 Conclusion: design, production and characterization methods 5 VLSI technology for hydrogel-based microfluidics 5.1 Overview of photolithography methods 5.2 Standard UV photolithography system for microfluidic structures 5.3 Self-made UV lithography system suitable for the mVLSI 5.3.1 Lithography setup for the DFR and SU-8 master exposure 5.3.2 Comparison of mask-based UV induced crosslinking for DFR and SU-8 5.4 Mask-based UV photopolymerization for mVLSI hydrogel patterning 5.4.1 Lithography setup for the photopolymerization of hydrogels 5.4.2 Hydrogel photopolymerization: experiments and results 5.4.3 Troubleshooting: photopolymerization of hydrogels 5.5 Conclusion: mVLSI technologies for hydrogel-based LoCs 6 Components for chemofluidic circuit design 6.1 Passive components in microfluidics 6.1.1 Microfluidic resistor 6.1.2 Planar-passive microfluidic signal mixer 6.1.3 Phase separation: laminar flow signal splitter 6.1.4 Hydrogel-based microfluidic one-directional valves 6.2 Hydrogel-based active components 6.2.1 Reversible hydrogel-based valves 6.2.2 Hydrogel-based variable resistors 6.2.3 CVPT: the microfluidic transistor 6.3 Conclusion: components for chemofluidic circuits 7 Hydrogel-based logic circuits in planar microfluidics 7.1 Development of a planar CVPT logic concept 7.1.1 Challenges of planar microfluidics 7.1.2 Preparatory work and conceptional basis 7.2 The microfluidic CVPT-RTL concept 7.3 The CVPT-RTL NAND gate 7.3.1 Circuit optimization stabilizing the NAND operating mode 7.3.2 Role of laminar flow for the CVPT-RTL concept 7.3.3 Hydrogel-based components for improved switching reliability 7.4 One design fits all: the NOR, AND and OR gate 7.5 Control measures for cascaded systems 7.6 Application scenarios for the CVPT-RTL concept 7.6.1 Use case: automated cell growth system 7.6.2 Use case: chemofluidic converter 7.7 Conclusion: Hydrogel-based logic circuits 8 Summary and outlook 8.1 Scientific achievements 8.2 Summarized recommendations from this work Supplementary information SI.1 Swelling degree of BIS-pNIPAAm gels SI.2 Simulated ray tracing of UV lithography setup by WinLens® SI.3 Determination of the resolution using the intercept theorem SI.4 Microfluidic master mold test structures SI.4.1 Polymer and glass mask comparison SI.4.2 Resolution Siemens star in DFR SI.4.3 Resolution Siemens star in SU-8 SI.4.4 Integration test array 300 μm for DFR and SU-8 SI.4.5 Integration test array 100 μm for SU-8 SI.4.6 Microfluidic structure for different technology parameters SI.5 Microfluidic test setups SI.6 Supplementary information: microfluidic components SI.6.1 Compensation methods for flow stabilization in microfluidic chips SI.6.2 Planar-passive microfluidic signal mixer SI.6.3 Laminar flow signal splitter SI.6.4 Variable fluidic resistors: flow rate characteristics SI.6.5 CVPT flow rate characteristics for high Rout Standard operation procedures / Der Transport von lebenswichtigen Nährstoffen in Flüssigkeiten sowie der Austausch spezifischer chemischer Signale von Zelle zu Zelle wurde in Milliarden Jahren natürlicher Evolution optimiert. Dieses Vorbild aus der Natur ist ein treibender Faktor im Fachgebiet der Mikrofluidik, welches die Manipulation kleinster Flüssigkeitsmengen erforscht um diese Effekte in fluidischen Mikrosystemen für technische Lösungen zu nutzen. Derzeit finden mikrofluidische Systeme vor allem in der Diagnostik, z.B. wie SARS-CoV-2-Antigentests, oder im Bereich der Hochdurchsatzanalyse, z.B. in der Krebsforschung, besondere Beachtung. Entweder einfach zu bedienende oder hochintegrierte mikrofluidische Systeme, die biologische und chemische Laboruntersuchungen auf einem sogenannten Lab-on-a-Chip (LoC) durchführen, bieten schnelle Analysen, hohe Funktionalität, hervorragende Reproduzierbarkeit bei niedrigen Kosten pro Probe und einen geringen Bedarf an Reagenzien durch die Miniaturisierung des Systems. Trotz des großen Fortschritts verschiedener LoC-Technologieplattformen in den letzten 30 Jahren mangelt es noch an standardisierten mikrofluidischen Komponenten sowie an einer leistungsstarken, vollintegrierten On-Chip-Automatisierung. Vielversprechend für das Design mikrofluidischer Systeme ist die Ähnlichkeit der Kirchhoff'schen Gesetze aus der Elektronik zur Vorhersage von Druck und Flussrate in Mikrokanalstrukturen. Ein spezifischer Ansatz der LoC-Plattformtechnologie steuert Flüssigkeiten durch aktive Polymere, die auf spezifische physikalische und chemische Signale in der Flüssigkeit reagieren. Analog zur (Mikro-)Elektronik können diese aktiven Polymermaterialien durch verschiedene fotolithografische und mikrostrukturelle Methoden realisiert werden, um funktionelle Elemente mit hoher Skalierbarkeit zu erzeugen.\\ Die sogenannten chemofluidischen Schaltungen haben ein hohes funktionales Potenzial und ermöglichen eine 'wirkliche' on-chip Automatisierung, sind jedoch komplex im Systemdesign. In dieser Arbeit wird ein fortgeschrittenes Schaltungskonzept für eine planare mikrofluidische Chiparchitektur vorgestellt, das aus der frühen Ära der halbleiterbasierten Resistor-Transistor-Logik (RTL) hervorgeht. Beginnend mit dem Stand der Technik der mikrofluidischen Technologien, werden Materialien und Methoden dieser Arbeit näher beschrieben. Daraufhin wird die bevorzugte Herstellungstechnologie bewertet und verschiedene mikrofluidische Komponenten werden in Funktion und Design diskutiert. Die wichtigste Komponente, die es zu charakterisieren gilt, ist der auf Hydrogel basierende chemische Volumen-Phasenübergangstransistor (CVPT), der den Schlüssel zur Realisierung mikrofluidische Logikgatteroperationen darstellt. Dieses Schaltungskonzept (CVPT-RTL) ist robust und einfach im Design und kann mit gängigen Materialien und Fertigungstechniken realisiert werden. Zuletzt werden Anwendungsszenarien für das CVPT-RTL-Konzept vorgestellt und Empfehlungen für die fortlaufende Entwicklung angestellt.:1 The transistor: invention of the 20th century 2 Introduction to fluidic microsystems and the theoretical basics 2.1 Fluidic systems at the microscale 2.2 Overview of microfluidic chip fabrication 2.2.1 Common substrate materials for fluidic microsystems 2.2.2 Structuring polymer substrates for microfluidics 2.2.3 Polymer chip bonding technologies 2.3 Fundamentals and microfluidic transport processes 2.3.1 Fluid dynamics in miniaturized systems 2.3.2 Hagen-Poiseuille law: the fluidic resistance 2.3.3 Electronic and microfluidic circuit model analogy 2.3.4 Limits of the electro-fluidic analogy 2.4 Active components for microfluidic control 2.4.1 Fluid transport by integrated micropumps 2.4.2 Controlling fluids by on-chip microvalves 2.4.3 Hydrogel-based microvalve archetypes 2.5 LoC technologies: lost in translation? 2.6 Microfluidic platforms providing logic operations 2.6.1 Hybrids: MEMS-based logic concepts 2.6.2 Intrinsic logic operators for microfluidic circuits 2.7 Research objective: microfluidic hydrogel-based logic circuits 3 Stimuli-responsive polymers for microfluidics 3.1 Introduction to hydrogels 3.1.1 Application variety of hydrogels 3.1.2 Hydrogel microstructuring methods 3.2 Theory: stimuli-responsive hydrogels 3.3 PNIPAAm: a multi-responsive hydrogel 4 Design, production and characterization methods of hydrogel-based microfluidic systems 4.1 The semi-automated computer aided design approach for microfluidic systems 4.2 The applied design process 4.3 Fabrication of microfluidic chips 4.3.1 Photoresist master fabrication 4.3.2 Soft lithography for PDMS chip production 4.3.3 Assembling PDMS chips by plasma bonding 4.4 Integration of functional hydrogels in microfluidic chips 4.4.1 Preparation of a monomer solution for hydrogel synthesis 4.4.2 Integration methods 4.5 Effects on hydrogel photopolymerization and the role of integration method 4.5.1 Photopolymerization from monomer solutions: managing the diffusion of free radicals 4.5.2 Hydrogel adhesion and UV light intensity distribution in the polymerization chamber 4.5.3 Hydrogel shrinkage behavior of different adhesion types 4.6 Comparison of the integration methods 4.7 Characterization setups for hydrogel actuators and microfluidic measurements . 71 4.7.1 Optical characterization method to describe swelling behavior 4.7.2 Setup of a microfluidic test stand 4.8 Conclusion: design, production and characterization methods 5 VLSI technology for hydrogel-based microfluidics 5.1 Overview of photolithography methods 5.2 Standard UV photolithography system for microfluidic structures 5.3 Self-made UV lithography system suitable for the mVLSI 5.3.1 Lithography setup for the DFR and SU-8 master exposure 5.3.2 Comparison of mask-based UV induced crosslinking for DFR and SU-8 5.4 Mask-based UV photopolymerization for mVLSI hydrogel patterning 5.4.1 Lithography setup for the photopolymerization of hydrogels 5.4.2 Hydrogel photopolymerization: experiments and results 5.4.3 Troubleshooting: photopolymerization of hydrogels 5.5 Conclusion: mVLSI technologies for hydrogel-based LoCs 6 Components for chemofluidic circuit design 6.1 Passive components in microfluidics 6.1.1 Microfluidic resistor 6.1.2 Planar-passive microfluidic signal mixer 6.1.3 Phase separation: laminar flow signal splitter 6.1.4 Hydrogel-based microfluidic one-directional valves 6.2 Hydrogel-based active components 6.2.1 Reversible hydrogel-based valves 6.2.2 Hydrogel-based variable resistors 6.2.3 CVPT: the microfluidic transistor 6.3 Conclusion: components for chemofluidic circuits 7 Hydrogel-based logic circuits in planar microfluidics 7.1 Development of a planar CVPT logic concept 7.1.1 Challenges of planar microfluidics 7.1.2 Preparatory work and conceptional basis 7.2 The microfluidic CVPT-RTL concept 7.3 The CVPT-RTL NAND gate 7.3.1 Circuit optimization stabilizing the NAND operating mode 7.3.2 Role of laminar flow for the CVPT-RTL concept 7.3.3 Hydrogel-based components for improved switching reliability 7.4 One design fits all: the NOR, AND and OR gate 7.5 Control measures for cascaded systems 7.6 Application scenarios for the CVPT-RTL concept 7.6.1 Use case: automated cell growth system 7.6.2 Use case: chemofluidic converter 7.7 Conclusion: Hydrogel-based logic circuits 8 Summary and outlook 8.1 Scientific achievements 8.2 Summarized recommendations from this work Supplementary information SI.1 Swelling degree of BIS-pNIPAAm gels SI.2 Simulated ray tracing of UV lithography setup by WinLens® SI.3 Determination of the resolution using the intercept theorem SI.4 Microfluidic master mold test structures SI.4.1 Polymer and glass mask comparison SI.4.2 Resolution Siemens star in DFR SI.4.3 Resolution Siemens star in SU-8 SI.4.4 Integration test array 300 μm for DFR and SU-8 SI.4.5 Integration test array 100 μm for SU-8 SI.4.6 Microfluidic structure for different technology parameters SI.5 Microfluidic test setups SI.6 Supplementary information: microfluidic components SI.6.1 Compensation methods for flow stabilization in microfluidic chips SI.6.2 Planar-passive microfluidic signal mixer SI.6.3 Laminar flow signal splitter SI.6.4 Variable fluidic resistors: flow rate characteristics SI.6.5 CVPT flow rate characteristics for high Rout Standard operation procedures

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